Vancouver police are concerned about a small group of violent activists who attended an otherwise peaceful anti-pipeline blockade training event this past weekend.

Those hoping to stop or delay future pipeline construction met in Vancouver for the event: "No Pipelines: Action Training for Climate Justice," which was hosted by Rising Tide – Vancouver Coast Salish Territories.

A spokesperson for the event said most participants are focused on non-violent ways to get their message across.

But the movement is attracting those just hoping to cause mischief.

One attendee, who gave his name as James Moore, said he would go as far as setting a cop car on fire to escalate the situation.

"Sure I'll do it," he said. "I don't care about the pipeline."

Police said they have been monitoring these groups and most of their demonstrations are peaceful, adding there is a danger movements like these attract people who want to start trouble.

"The recent Stanley Cup riots are the best comparison," said spokesperson Const. Brian Montague. Immediately following the riot, Mayor Gregor Robertson blamed the bedlam on a “small number of hooligans on the streets of Vancouver causing problems.”

Stephen Collis, who agreed to speak for the group, wanted to make it clear the majority want peaceful protests.

"That's someone here to participate. Not someone any of us know," Collis said of the attendee prepared to engage in criminal acts.

Freda Huson, a spokesperson for the Unis'tot'en clan who spoke at this weekend's events, echoed Collis' view in a press conference Monday.

"We're not criminals, we're not looking for violence," she said.

Police say they are also concerned about anti-pipeline graffiti recently painted on bus shelters and around the city.